As an architect, I sometimes am asked to provide a "digital seal" to my pdf drawings to prove that I personally have created the file and to provide verifiable proof that the file has not been changed since I created it. It is to serve the same function as my embossed seal on a sheet of paper, symbolically saying, "this is mine, don't change it". Does Adobe Reader do this? I've read the documentation on digital signatures, but still unsure if AReader can apply a digital signature with verifiable proof of an unchanged document. I have found 3rd party software for a price that claims to do it, but if AReader will do it, I'd prefer to stay within a single program.

does anyone know how to create 2 digital signatures to apply to one document. for example, if you are filing a joint income tax return and both parties need to sign it...then how do you create 2 separate digital signatures for the one document. i am using Adobe Reader 8.
any advice would be most welcomed.
thanx.
bob

does anyone know how to create 2 digital signatures to apply to one document. for example, if you are filing a joint income tax return and both parties need to sign it...then how do you create 2 separate digital signatures for the one document. i am using Adobe Reader 8.
any advice would be most welcomed.
thanx.
bob

If you mean you want to add what appears to be script linework on the IRS signature line so it looks like you've personally signed it, I'd do this. I'd "print" the IRS form using a free PDF printer such as the one included with PDFill to make a pdf of the 1040. Then, you and spouse sign a blank paper with names an appropriate distance apart to match the form. Scan the names and save as jpg or other format. Use a free program such as PDFill and use their merge tool to add the signature image to the IRS pdf as a watermark below the IRS pdf. You can size the image by percent and locate from edges by inches, so can move the signatures so they appear to be as if signed on the form. If you want a true security style "digital signature" where there is a binary code security system to prove your identity and prevent document changes, that's another whole issue. Somebody else can answer that one.

Your best bet is to create a Custom Signature Appearance and use a digital rendition of your stamp as the appearance. Select the Edit > Preferences (Win) or Reader > Preferences (Mac) menu item. From the Preferences dialog select Security from the list view on the left. Click the New button in the Appearances group box to bring up the Configure Signature Appearance dialog. Select the Imported graphic radio button and then click the File button to browse for the image of your seal. The default file format is PDF, so if you need to look for a different kind of file be sure to select it from the drop-down menu.